What truck should I get?

So I've got 20k to spend on a truck. Its primary purpose will be to tow our 16ft enclosed around tow and also serve as my daily driver outside of work. I live in Birmingham, AL so there are a lot of hills around here. I'm looking at 2500HDs, F-150s, and 1500s. I need something that is going to hold up to the abuse of a maintenance vehicle and give us a long life span.